Electric lamp.



H. A.. DOUGLAS,

ELECTRIC LAMP. APPLIoATmN FILED human, 1012.

fem"

Patented July 22 Y`l`TIIFED S'Taalisgpgrnnr OFFICE.

naam' n. DOUGLAS, orh CHICAGO, ILLINOIS.

ELECTRIC LAMP.

Specication of Letters Patent.

Application filed March 20, 1912. Serial No. 685,023.

i, To all 'whom it may concern;

Be it known that l, HARRY A. Domains, citizen of the United States, residing at Chicago, in the county of Cook and State of lllinois, have invented a certain new and useful Improvement in Electric Lamps, or which the following is a full, clear, concise, and exact description, reference being had -to the accompanying drawings, forming. a

part of this specification.

My invention relates to electric lamps and l has for one of its objects thel provision of improved mechanism whereby circuit connections with the. lampsflnayI readily be cfs footed. f

My invention is also of se-rvice in connection with those electric lamps which are to be brought into focus with some light dis tributing elements, such as reflectors.

When my invention is thus embodied, im, proved means are presentwhereby the lamps may readily be focused.

I will` explain the various characteristics of noyinvention by reference to the accompanying drawing showing the preferred eni bodiment thereof, to which embodiment l do'not wish to beliniited, and in which drawing;- I

Figure l is a side view or a lamp structure made in accordance with theinven tion, the redector forming a part of the structure being only partially shown; Fig. 2 is a view similar to Fig..1, excepting that the reflector portion and an inclosing shell are shown in,1section; Fig. 3 is a View simi lar to Fig. 2 showing some of the parts in diere'nt positions; Fig. 4:- is a viewon line 4l 4 of Fig. 2, some of the parts being shown in full elevation; Fig. 5 is `a sectionalview on line 5 5 of Fig. 4; Fig. 6 is a sectional v view on line 6 6 of Fig. 2; Fig. 7 is a sectional view online 7 7 of Fig. 2; and Fig. 8' is a sectional view online 8 8 otf- Fig. 2.

like parts are indicated by similar char acters of reference throughout vthe different gures.-

The lamp bulb l incloses a lighting fila- Y ment 2 which is connected with terminals 3 3 upon the exterior of the bulb, these terminals being mounted upon an insulating base Il that. also constitutes a mounting for the lamp bulb l. The mounting base 4 is desirably provided with a metallic sheath 5, a pin' proj ect-ing diametrically through the mountingbase Il and extending beyond the sheath 5 upon both sides as illustrated clearlyv in Figs. Il and 6. The ends of the pin (iconstitute elements oi bayonet catches, theI complementa] elements of such catches being formed in athreaded sleeve 7 that is in threaded engagement with the thread` ed interior of a containing shell S. The base l of the lamp may be slipped avithin the sleeve 7 when the projecting ends'of the piu 6 are placed in vertical alinement with the vertical .branches of the bayonet slots 9. When the outer ends of the pin 6 are in cngagement with the bayonet slots 9, the shell 7 maybe turned for the purpose of withdrawing the lamp or locating it in position. ln the embodiment of the invention illustrated, toy which embodiment-'l do not wishy `sleeve 7 are to be turned. l

The terminals Bot' the lamp are in the form of elongated parallel contact plates, as indicated in Figs. l and 5, these plates being ehgaged byterrninal posts 10 when the lamp is to be adapted for inclusion in circuit. The terminal posts l0 are carriedy by al plunger l1 located within the shell S, this plunger being upwardly spring pressed by means of a coiled spring l2 interposed be tween the'inturned base of the shell 8 and said plunger. The plunger is desirably prevented from rotationby means of an 0utsetting pin 13 carried thereby, this pin working within a vertical slot 14 provided in the shell 8. The terminal posts 10 are made hol low at their bases by means of axially disposed recesses that ar' .designed to receive the ends of current conducting wires for bringing about circuit association of the lamp with a suitable source of current, binding screws 15 passing partially through the postsa() and being adapted for clamping engagement with the wires introduced into the bases of said posts aswill be readily un- ,derstood by particular reference to Figs.

5 and 8.

When the lamp is to be'placed in circuit Y connection with the posts 10, the plane in which these posts lie should extend across the contact plates 3, as indicated in Fig. 5, theplates 3 being sufficiently separated so that neither of them can be engaged with the two posts at the same time, whereby short circuiting is avoided. In order that the person who is manipulating the lamp may know whether or not the posts 10 are in engagement with the plates 3, I provide a structural characteristic that serves to convey an indication to the manipulator, this structural characteristic residing in a recess V16 extending upwardly from the lower margin of the sleeve 7, the pin 13 rising slightly within the slot or recess 16 upon the completion of each revolution of the sleeve 7, the spring .12 causing this result; When the pin 13 so rises the manipulator Vknows that the posts 10 are in Contact with the plates 3. If the lamp has not been inserted to a suiicient extent withinthe shell 8 its base 4 may befurther turned until the pin 13 is again slightly raised within the slot 16, this operation being continued until the sleeve 7 has been suiicient-ly inserted within the shell 8, the posts 10 in riding over` the contact plates 3 keeping the contacting surfaces of the plates and posts bright whereby good circuit contacts are assured between said posts and plate.

.When downward pressure upon the lamp 1 is removed (this downward pressure continuing during the time the sleeve 7 is being turned to hold the pin 6 in the position illustrated in Fig. 3) the pin- 13 being in alinement with the slotl 16, the spring 12 distends and forces the'pin 13 upwardly into the slot 16 and forces into engagement with the locking portions the ends of pin 6 of the bayonet lslots 9. The lamp is thus held from rotation bythe operation of the spring 12, the pin 6 and the locking portions of the bayonet slots engaging said pins, the contact plates being in individual contact with the posts 10. AThe contact posts are instantly held from rotation by the pin The pin 13 serves an additional function, when engagingY the slot 16 upon the release of the lamp 1, which is to hold the sleeve 7 from rotation, a result ,Which' is accomplished by the reception ofthe pin 13 within the slot 16. .In this way the contact plates 3 are held in connection with the posts l0, the pin 6 Iserving merely to prevent rotation of v the lampl with respect to the sleeve 7. The shell 8 carries .a reflector 17, only partially with respect to may readily be which has been shown for the lack of space, which reflector the lamp 1 focused bythe construction described. i

It willbeobserved that the lamp is adjustable from within the reflector rather than4F upon the` exterior thereof and rather than upon the exterior of the shell inclosing parts of the lamp structure.

While I have herein shown and particularly described thepreferred embodiment of my invention, I do not wi'shto be limited to the precise details o f constructionshown as changes may readily be made without departing from the spirit of my invention. 1 Having thus described' my invention, I

claim as new and desire to secure by Letters Patent the following l. An electric lamp structure including a shell; a sleeve in threaded engagement with located within the shell; lcontact posts adapted for connection with circuit wires and carried by said plunger; a pin projecting from said plunger, there being a slot in the shell with which the latter pin engages for preventing the rotation of the plunger, said sleeve being provided with a slot in its lower portion for engaging said pin to prevent the rotation of the sleeve; and a spring .interposed `between the bottom portion of the shell and said plunger, 'the aforesaid bayonet slo-t and the-pin for engaging it beingso related to the slot in the lower portion of the sleeve'and'the. pin 1n engagement f with saidslot as to maintain engagement, between said contacts and posts, the aforesaid bayonet slothaving a lower depression. to enable the bayonet slot engaging pin to.

engage 4the sleeve for the purpose of effect- A ing the rotation of said =sleeve. Y

2. An electric lamp structure including a shell; a sleeve in threaded engagement with the interior of. the shellv and provided with 'a bayonet slot;` a lamp provided with a base; v

a pin carried'by the lamp base and adapted for engagement with said bayonet slet; a

pair 'of contacts carried upon the bottom of .the base; a plunger below located within` the shell; contact posts adapted for connection with'y circuit wires and carried by said plunger; a pin project ing from said plunger, there being a slot in the shell with which the latter pin engages the lamp base andw for preventing the lrotation of the plunger,

said sleevebeing provided witha slot in its lower portion for engaging said pin to prevent the rot-ation of thesleeve; and a spring interposed between the bottom portion of the shell and s aid plunger, the aforesaid bayonetslot and the pin for engaging it being so related to the slot in the lower portion of the sleeve and the pin 1n engagement with said slot as'to maintain engagement between said contactsand posts.

' 3. An electric lamp structure including a lamp bulb having a base which carries lamp terminal contacts; a shell inclosing said base, there being a threadedistructure intervening between the lamp and shell whereby the lamp may be moved in and out upon being turned with respect to/,the shell; a plunger within the shell and disposed between said base and the end of the shell opppsite to that end where the lamp bulb is disposed; a pair of -contact posts adapted for connection with current conducting wires and carried by said plunger; a spring inclosed by the shell and in enga ement therewith and with the plunger for i orcing the contact posts into engagement with the contacts carried by the lamp base; and means for holding the lamp base and plunger fromrelative rotation when said posts are in engagement with the contacts carriedpby the lamp base. i

4. An electric lampcstructure including a lamp bulb having a base which carries lamp terminal contacts; a shell inclosin-g said base, there being a threaded structure intervening between the lamp and shellwhereby the lamp may be moved in and out upon being turned with respect to the shell; a plunger within the shell and disposed between said base and the end of the shell opposite to that end where the lamp'bulb disposed; a pair of contact posts adapted for connection with current conducting wires and carried bysaid plunger;and a spring inclosed bythe shell and in engagement therewith and with the plunger for forcing the contact posts into engagement with the contacts carried ,by the lamp base.

5. An electric llamp structure including a lamp bulb having a base which vcarries lamp terminal contacts; a shell within which the' lamp base may be movedto vary the extent to which the lamp basefis received within the shell,` there being means `for holding the lamp base in various positions within the shell; a plunger within the shell and disposed between said base and the end of the shell opposite to that end where the lampV bulb is disposed; a pair of contact posts adapted for connection with current conducting wires and carried by said plunger; and a spring inclosed by the shell and in engagement therewith 'and with the plunger for forcing the* contact posts into engagegient with the contacts carried by the lamp ase.

6. An electric lamp structure including a lamp bulb having a base which carries lamp terminal contacts; a shell inclosing the lamp base, there being a threaded structure intervening between the lamp'and shell whereby the lamp may be moved in and out upon being turned with respect to the shell; a

- plunger'within the shell and disposed between said base and the end of the shell yopposite to that end where the lamp bulb is disposed; a pair of contact posts adapted .for connection with current conducting wires and carried by said plunger; and a, spring inclosed by the shell and in engagement therewith and with the plunger for forcingv the contact posts into engagement with the contactscarried by the lampbase. 7 An electric lamp structurev including a I lamp bulb having a base which carries lamp terminal contacts; a shell inclosing the lamp base, there being a threaded structure intervening between the lamp and shell whereby the lamp may be moved in andout upon being turned with respect to the shell; a plunger within the shell and carrying contacts adaptedto be engaged with the aforesaid contacts; and a spring for pressing the plunger toward the lamp base to effect engagement between the contacts carried by the plungernand the contacts carried by the lamp base'.l

8. An electric lamp structure including a lamp bulb; .a shell within.whicl1' the base\of the lamp bulb projects, there being a threaded structure intervening between the lamp and shell whereby the lamp may be moved in and out upon being turned with respect to the shell, the lamp bulb being thus-ad justable longitudinally of the shell; and mechanism operating within said Shell for holding the lamp bulb in diifering positions with respect to the shell.

` 9. An electric lamp structure including a shell; a reflector supported thereby; a. lamp bulb whose base is received withthe shell,

there'being althreaded structure intervening between the lamp and shell whereby the lamp may be moved in and out upon being turned withv respect to the shell, the lamp bulb being thus adjustable longitudinally of said shell, it being accessible from within the reflector for the purpose of itsadjustment with respect to the shell and with respect to the reflector; and mechanism operating within the shell for holding the lamp bulb in differing positions with respect to the shell.

10. An electric lamp structure including a lamp bulb having a contact carrying base; a shell; an element in threaded connection with the shell and receiving the lamp base,

this element by being rotated with rpect to the shell effecting focal adjustment of the shell to maintain focal adjustment ofl the lamp, said lamp being movable longitudinally of the threaded element and then serving to operate upon said means to break the fixed relation of the threaded element and shell to permit of rotation of the threaded element to effect focal adjustment of the lamp.

In witness whereof, I hereunto subscribe my 11a-me this fourteenth day of March A. D., 1912'.`

HARRY A. DOUGLAS. Witnesses:

E. L. WHITE, G. L. CRAcG. 

